U.S. Pat. Nos. 5,236,135 and 5,240,187 disclose methods and apparatus for the treatment of solid and non-solid (soft) biological waste materials that permits the collection of such biological waste at the point and at the time of its generation in a container, which is subsequently transported for pulverization, decontamination and safe disposal. A separate portable processing chamber, with an integral means to treat biological waste, is used at locations remote from a main power unit for the collection of biological waste and is then moved to the location of the main power unit to drive the waste-treatment means carried within the chamber. The separate portable processing chamber includes a closable chamber, a rotatable waste treatment system carried within the chamber and a plurality of pivotable blades carried by the rotatable system which interact with the biological waste and surfaces formed on the chamber walls and provide effective disintegration and blunting of solid waste, cutting and mincing of non-solid waste, and decontamination of the biological waste within the processing chamber.
While biological waste can be effectively treated by the method and apparatus of U.S. Pat. Nos. 5,236,165 and 5,240,187, treated biological waste particles can sometimes adhere and cling to the under surfaces of the cap or lid that closes the processing chamber, and such waste particles can drop uncontrollably from the cap or lid as, or after, it is removed from the apparatus. Although such biological waste will generally be decontaminated as a result of its treatment within the processing chamber, its escape onto adjacent surfaces requires clean-up and is undesirable. In addition, if the processing chamber is mistakenly opened before treatment and decontamination of the biological waste is completed, the escape of such biological waste can require special precautions to avoid exposure of personnel to undecontaminated and possibly infectious biological waste.
To further safeguard the personnel handling the processing and disposal of such biological waste, it is desirable to have an indication that the decontamination agent was present in the treatment process, or when decontamination of the biological waste has been effected.